Abstract: An air pressurizing and purging system for electrical equipment contained in compartments with safety checks and interlocks ensuring inhibition of main power circuit completion until purging pressure and fan operation are verified by a timer for a set period.System failure initiates a trip after a delay to open the main power circuit.Re-energization of the main circuit requires full purge and verification procedure once more.

Abstract: Winding mechanism for example for cranes in which a winding drum is rotatable by two motors the first arranged to drive the drum so as to take up any slack rope when operating conditions, for example sea-state, reduce the load on the drum, the other motor driving the drum through an over-run device. If required the first motor is controllable in response to the difference between signals from the winding drum and a sensing drum in a manner to reduce the difference to zero to ensure motion of the winding drum in sympathy with motion of the messenger drum.

Abstract: In a friction welding machine a shear tool is provided for shearing flash off the welded workpieces at the weld zone which tool is interposable between one workpiece holder and the flash only after the workpiece holder and the flash have been relatively moved apart. The workpiece holder and the weld zone are then relatively moved towards one another to force the shear tool and the weld zone to traverse relative to one another so that the flash is completely sheared off the weld zone.

Abstract: In a friction welding machine reaction loads are borne by a strut member and tie means. The strut member and tie means are interconnected by beam elements which support the workpieces against loads acting along the axis of relative rotation of the workpieces.The machine has a ram which forces the workpieces together. One workpiece is held by a holder guided for movement along the strut member. One beam element is connected to the ram and the other to a support for the other workpiece. The tie means are connected to the beam elements intermediate the ends of the beam elements.The strut member is not subject to any significant bending loads arising from reaction forces so that accurate alignment of the workpieces on the axis of relative rotation is maintained.

Abstract: Orbital welding apparatus in which wire is fed to the welding zone by wire feed mechanism operable by differential rotation of two one-piece U-shape drive members operable at different speeds, one member carrying a welding electrode and the wire feed mechanism.Both drive members have openings allowing entry of tube to be welded. The apparatus permits orbital welding of very closely spaced tubes without using a wire feed drive motor mounted on the rotatable assembly. Both TIG or MIG arc welding methods may be performed by the invention, or any method involving the feeding of wire into the weld zone.

Abstract: A rope connected to a chain cable by a connector is recovered using a chain cable lifter wheel. The connector is shaped to pass over the wheel, which has a groove for the rope. The wheel has pockets which can receive the connector and also receive chain cable links. Protuberances on the connector and stops in the pockets ensure correct seating of the connector in a pocket so as to ensure correct subsequent engagement of chain links with the pockets of the wheel.

Abstract: Orbital welding apparatus in which wire is fed to the welding zone by wire feed mechanism operable by differential rotation of two drive members operable at different speeds, one member carrying a welding electrode and the wire feed mechanism. Both drive members have openings allowing entry of tube to be welded. The drive members cooperate with auxiliary drive members which fit into the respective openings in the main drive members. The auxiliary drive members are guided across an opening in a housing enclosing the drive members by means of a bridge piece securable to the housing across the opening. The apparatus permits orbital welding of very closely spaced tubes without using a wire feed drive motor mounted on the rotatable assembly. Both TIG or MIG arc welding methods may be performed by the invention, or any method involving the feeding of wire into the weld zone.

Abstract: A recirculating type atomizer which has a body, a discharge orifice in one end of the body and a lance, movable in the body having a tip for closing the discharge orifice, is provided with electrical circuit means for indicating when the orifice is closed. The circuit means is formed in part by the body and the lance, the rear end of the lance being electrically insulating from the body so that the circuit means is only completed when the tip of the lance closes the orifice.